The Combined Effect of Biochar and Mineral Fertilizer on Triticale Yield, Soil Properties under Different Tillage Systems

This study examined the effect of study time, biochar dose, and fertilization-tillage system on the improvement of sandy loam physical-chemical properties and triticale grain yield. The soil properties (water holding capacity (WHC), wettability, moisture content (MC), organic matter content (SOM), pH, and electrical conductivity (EC) were monitored in short time intervals (after 3, 6, 12, and 24 months). Soil was tilled in two methods (shallow ploughless tillage and direct drilling), fertilized with nitrogen, phosphorus, and potassium (NPK) fertilizers, and amended with three hydrophobic pine wood biochar doses (0 t/ha; 5 t/ha; 15 t/ha). It was found that 15 t/ha biochar dose had the highest effect on the soil’s physical-chemical properties improvement (SOM increased by 33.7%, pH—by 6.84%, EC—by 23.4%, WHC—by 8.48%, and MC—by 21.8%) compared to the variants without biochar. Direct drilling, fertilization with NPK fertilizers and 15 t/ha biochar dose significantly influenced the rise of soil’s physical-chemical properties and triticale yield (3.51 t/ha).


Introduction
The surface properties of soil have a high practical impact. They are closely interdependent. It is well known that many processes of interaction between soil particles with the outer environment occur through water which usually surrounds these particles in natural conditions. Interaction between solid material and liquid phases is one of the most important soil processes which include physical, chemical, and biological functions of soil [1]. Wettability is one of the most often occurring phenomena which arise between the surface boundaries of different phases [2]. It is a fundamental property controlling the wetting of plane and granular solid materials. Compared with the plane surfaces of the solid, wettability of granular materials has additional complexity of different level roughness effects (particle level or particle agglomeration level). The wettability of soil affects hydrological functions of soil systems including infiltration, preferential flow, and runoff. Control of surface wettability is equally important in various industrial applications [3]. Life and agricultural sciences pay much attention to the soil infiltration problem when the occurrence of hydrophobicity of soil decreases or temporarily weakens infiltration, which enhances runoff, erosion, or sedimentation of the surface.
It is known that soil wettability depends on its number of mineral/organic compounds and composition, fractions of different structures (sand, clay particles). Previous studies [2] found that the mineral part of the soil is characterized by the hydrophilic surface properties and organic matter which is described by the amphiphilic compounds and nonpolar organic components of the surface adsorbed on the surface of the particles and thus governing hydrophobicity of the soil solid phase. Free lipids including fatty acids, alcohols, alkanes, and suberin which are excreted from the plant roots all together contribute to the typically result in higher soil organic matter, reduced erosion, increased infiltration, and increased water-stable aggregates compared to traditional tillage practices. The impact of biochar on the soil quality in different management systems is not well understood yet.
Triticale is a hybrid of wheat and rye that has been harvested due to a combination of positive wheat properties (yield efficiency, grain quality) and rye properties (disease resistance and durability) [18]. Triticale has been found to grow better than wheat in poor-quality soils. To date, triticale is mainly grown as fodder, cover crop, and for biogas production. Triticale is considered an interesting species that can be useful for cultivation even in unfavorable biotic and abiotic conditions [19]. Compared to wheat, triticale adapts better to a variety of soil and environmental conditions and can provide higher grain yields. Several factors influence the yield of triticale grains: local climatic and soil properties, uptake of mineral components, and appropriate methods of plant protection against diseases, pests, and weeds.
At present, there is not much information on the factors influencing triticale yield. In order to improve tillage practices, it is necessary to identify soil properties that control the variation of triticale grain yield. This study was conducted to determine the variation of selected soil physical and chemical properties from the field study and to evaluate the soil property that could explain the triticale grain yield. The objective of this study was to determine the effect of hydrophobic pinewood biochar dose and tillage-fertilization system on the improvement of sandy loam physical-chemical properties and triticale yield. Hypothesis-direct drilling, fertilization with NPK fertilizers, and 15 t/ha biochar dose has the highest effect on the improvement of sandy loam physical-chemical properties and triticale yield. Detailed and accurate information about the soil allows more precise control of soil properties and more cost-effective distribution of soil amendments.

Plot Description, Scheme
The experiment was conducted in the Institute of Agriculture at Lithuanian Research Centre for Agriculture and Forestry and in the Research Institute of Environmental Protection at Vilnius Gediminas Technical University (Vilnius Tech). The investigation was conducted in 2019-2021 (55 • 23 N and 23 • 51 E) in the long-term (20 years) soil tillagefertilization systems field experiment. The soil was sandy loam (Endocalcari-Epihypogleyic Cambisol (FAO, 1998)). According to soil texture, this soil had the highest amount (53.7%) of sand (2-0.05 mm) particles, average amount (32.6%) of silt (0.05-0.002 mm) particles, and the lowest (13.7%) amount (<0.002 mm) of clay particles.
Research scheme: Factor A-soil tillage-fertilization system: • S-1-ploughless shallow tillage (stubble cultivation at 10-12 cm + pre-sowing cultivation at 5-6 cm) and no fertilization with NPK fertilizers; Biochar was incorporated into the soil before the sowing of summer triticale (Triticum x Secale) (on the 16 April 2019) during direct drilling with disc drill having a rotary tiller. The target yield of the summer triticale was 5 t/ha. Pine wood biochar (450 • C, 2 h) was used in the field experiment. Mineral fertilizers were applied: ammonium nitrate (34.5%), granular superphosphate (19%), and potassium chloride (60%). The experiment was arranged in a randomized complete block design with three replications (details of the experiment).
According to the meteorological data, March was the coldest month in the studied period of time (March-August) on the average (3.3 • C; long-term average -0.6 • C), and June was the warmest month (20.6 • C; long-term average 15.7 • C). There was no precipitation in April (long-term average is 37.6 mm), and the highest amount of precipitation was in August (35.67 mm; long-term average 73.2 mm) ( Figure 1). In the summer season, June was the driest month (20.6 • C and 5.37 mm); therefore, during the experiment, soil became completely dry, and at the end of summer (in August) the highest amount of precipitation was observed compared to the overall studied period. Biochar was incorporated into the soil before the sowing of summer triticale (Triticum x Secale) (on the 16 April 2019) during direct drilling with disc drill having a rotary tiller. The target yield of the summer triticale was 5 t/ha. Pine wood biochar (450 °C, 2 h) was used in the field experiment. Mineral fertilizers were applied: ammonium nitrate (34.5%), granular superphosphate (19%), and potassium chloride (60%). The experiment was arranged in a randomized complete block design with three replications (details of the experiment).
According to the meteorological data, March was the coldest month in the studied period of time (March-August) on the average (3.3 °C; long-term average -0.6 °C), and June was the warmest month (20.6 °C; long-term average 15.7 °C). There was no precipitation in April (long-term average is 37.6 mm), and the highest amount of precipitation was in August (35.67 mm; long-term average 73.2 mm) ( Figure 1). In the summer season, June was the driest month (20.6 °C and 5.37 mm); therefore, during the experiment, soil became completely dry, and at the end of summer (in August) the highest amount of precipitation was observed compared to the overall studied period.

Soil Sampling and Methodology for Hydro-Physical and Chemical Properties Determination
Soil samples were collected in four periods: 3, 6, 12, and 24 months after biochar application. Soil chemical and hydro-physical analyses were performed in the Research Institute of Environmental Protection. Soil samples were taken using a soil auger from every treatment from 0-15 cm soil layer. Plant residues were removed from samples before the analysis. Soil samples were dried in ambient conditions at 20 °C temperature and sieved through a 2 mm diameter sieve. The particle size distribution in soil samples was determined by using the volumetric particle size distribution method [20]. The wettability of soil was assessed by using the water drop penetration time test which is required for the complete drop infiltration [21]. The water holding capacity (WHC) of soil was determined and calculated according to the Formula (1) [22].

Soil Sampling and Methodology for Hydro-Physical and Chemical Properties Determination
Soil samples were collected in four periods: 3, 6, 12, and 24 months after biochar application. Soil chemical and hydro-physical analyses were performed in the Research Institute of Environmental Protection. Soil samples were taken using a soil auger from every treatment from 0-15 cm soil layer. Plant residues were removed from samples before the analysis. Soil samples were dried in ambient conditions at 20 • C temperature and sieved through a 2 mm diameter sieve. The particle size distribution in soil samples was determined by using the volumetric particle size distribution method [20]. The wettability of soil was assessed by using the water drop penetration time test which is required for the complete drop infiltration [21]. The water holding capacity (WHC) of soil was determined and calculated according to the Formula (1) [22].
The soil moisture content (MC) was calculated according to Formula (2) [22]: The soil pH was determined in soil: water suspension at ratio 1:1 using a pH meter [23]. The soil electrical conductivity (µs/cm) was also determined in soil: water suspension at ratio 1:1 according to the volume and using an electrical conductivity meter. The results of electrical conductivity represent the concentration of salt in the water of soil pores. The soil organic matter (SOM) was determined using the soil combustion method which is justified by dry (at 105 • C) soil combustion (at 550 • C), when constant sample weight is gained. The amount of SOM was calculated according to the mass difference before and after the combustion [24].

Biochar Production and Methodology for Determination of Its Physical-Chemical Properties
Biochar was produced from pine wood biomass at 450 • C temperature and 2 h holding time in a muffle furnace (SNOL2000/2002, SnolTherm, Utena, Lithuania). For the analysis of the water drop penetration time test, 10 small droplets (0.04 mL) were laid down on the plane and dry biochar surface using a laboratory pipette, and time for the complete water drop penetration time (WDPT) was assessed. Biochar wettability can be classified as: hydrophilic (WDPT < 5 s), slightly hydrophobic (WDPT 5-60 s), strongly hydrophobic (WDPT 60-600 s), severely hydrophobic (WDPT 600-3600 s) and extremely hydrophobic (WDPT > 3600 s) [21]. For the determination of biochar pH, samples were mixed with 0.1 N KCl solution at a ratio of 1:10 [25]. After 10 min of shaking, the pH in biochar suspension was determined using a pH meter. For biochar electrical conductivity analysis, 20 g of the sample was placed in 200 mL of desalinated water and shaken for 1 h and then the solution was filtrated. Electrical conductivity was assessed in filtered water using a conductometer [26]. The biochar cation exchange capacity was analyzed using the ammonium acetate exchange method. Biochar elemental composition (C, H, N, O, S) was determined using a EuroEA3000-Single analyzer (EuroVector, Milan, Italy) [27]. The sample (dried and milled of 0.5-3 mg) was weighted directly into the small capsule which then was placed into the elemental analyzer. Concentration of potentially toxic elements (Pb, Zn, Cu, Cr, Cd and Ni) in biochar was analyzed using an atomic absorption spectrometer (AAS) (Buck Scientific, Norwalk, CA, USA). Dry biochar samples were combusted at 450 • C for 2.5 h until ashes. Then, every sample of 0.5 g was weighted and mixed with 3 mL of 65% of nitric acid and 9 mL of 37% of hydrochloric acid. After that, the solution was placed into the Milestone ETHOS acid digestion system (Milestone Srl, Milan, Italy). After the process, the obtained solution was placed into the flask, filtered, and diluted with deionized water until 50 mL [27]. After the filtration, the concentration of potentially toxic elements was determined using the AAS [28]. The biochar surface functional groups were determined using Fourier-transform infrared spectroscopy (FTIR) when wavelengths from 4000 to 450 cm −1 were used [29]. The biochar specific surface area was analyzed according to N 2 -Brunauer-Emmett-Teller (BET) theory and BET analyzer (Quantachrome Instruments, Boynton Beach, FL, USA) [30].

Comparative Characteristics of Pine Wood Biochar Physical-Chemical Properties
Pine wood low-temperature (450 • C) origin biochar had a high hydrophobicity feature (WDPT = 1810 s) which was higher compared to birch wood and hemp biochar, but lower than pine bark biochar (Figure 2a). Hydrophobic biochar in this study had a low specific surface area (2.77 m 2 /g; Figure 2d), low O content (3.39%; Figure 2f), high ash content (16.6%; Figure 2b), high electrical conductivity (8.28 µs/cm; Figure 2c), higher C concentration (88.7%; Figure 2e) and slightly higher pH (8.53; Table 1) compared to slightly hydrophobic birch wood and hemp biochar types and extremely hydrophobic pine bark biochar. The high hydrophobicity of pine wood biochar can be related to higher ash content which blocks pore space and inhibits water entry through the biochar surface. pine bark biochar. The high hydrophobicity of pine wood biochar can be related to higher ash content which blocks pore space and inhibits water entry through the biochar surface.    Biochar types with higher initial ash content are less suitable for the soil amendment due to high amounts of potentially toxic elements (PTEs) which can cause soil pollution [31].
According to concentrations of potentially toxic elements, analyzed pine wood biochar corresponded to standard biochar quality considered in the European Biochar Certificate (EBC) in the case of five PTEs: Pb concentration was by 3.83 times lower compared to the standard biochar quality according to the maximum permissible Pb concentration (MPC, 150 mg/kg), Zn was 1.23 times lower, Cr was 8.39 lower, Cu was 3.89 times lower and Ni was 5.36 times lower (Figure 3a,b). According to cadmium concentration (2.48 mg/kg), the analyzed biochar slightly exceeded standard biochar quality limits according to the MPC (1.5 mg/kg). Some researchers claimed that Zn, Cu, and Pb are stabilized into the biochar [31]. For the long-term biochar application into the soil, it has to be carefully analyzed due to potentially toxic elements (PTEs) which can accumulate into the soil. According to the European Biochar Certificate, biochar cannot exceed the limit values of PTEs having an intention for its incorporation into the soil [32]. Biochar types with higher initial ash content are less suitable for the soil amendment due to high amounts of potentially toxic elements (PTEs) which can cause soil pollution [31]. According to concentrations of potentially toxic elements, analyzed pine wood biochar corresponded to standard biochar quality considered in the European Biochar Certificate (EBC) in the case of five PTEs: Pb concentration was by 3.83 times lower compared to the standard biochar quality according to the maximum permissible Pb concentration (MPC, 150 mg/kg), Zn was 1.23 times lower, Cr was 8.39 lower, Cu was 3.89 times lower and Ni was 5.36 times lower (Figure 3a,b). According to cadmium concentration (2.48 mg/kg), the analyzed biochar slightly exceeded standard biochar quality limits according to the MPC (1.5 mg/kg). Some researchers claimed that Zn, Cu, and Pb are stabilized into the biochar [31]. For the long-term biochar application into the soil, it has to be carefully analyzed due to potentially toxic elements (PTEs) which can accumulate into the soil. According to the European Biochar Certificate, biochar cannot exceed the limit values of PTEs having an intention for its incorporation into the soil [32]. Biochar had eight peaks which shows the existence of some functional groups in the biochar structure: alcoholic -OH (3442 cm −1 ), acidic C=O (1684 cm −1 ), aromatic C=C (1684 cm −1 , 1584 cm −1 , 1429 cm −1 ), anhydride C-O (1174 cm −1 ) and aromatic C-H (805 cm −1 , 879 cm −1 , 752 cm −1 ) ( Figure 4). FTIR spectrum of initial biochar showed strongly condensed biochar structure which can be seen from intensive C=C ring region [33]. It shows the growth of biochar aromaticity during the pyrolysis process. A rise in the peak at 879 cm −1 wavenumbers is related to C-H group deformations. Biochar had eight peaks which shows the existence of some functional groups in the biochar structure: alcoholic -OH (3442 cm −1 ), acidic C=O (1684 cm −1 ), aromatic C=C (1684 cm −1 , 1584 cm −1 , 1429 cm −1 ), anhydride C-O (1174 cm −1 ) and aromatic C-H (805 cm −1 , 879 cm −1 , 752 cm −1 ) ( Figure 4). FTIR spectrum of initial biochar showed strongly condensed biochar structure which can be seen from intensive C=C ring region [33]. It shows the growth of biochar aromaticity during the pyrolysis process. A rise in the peak at 879 cm −1 wavenumbers is related to C-H group deformations.

Statistical Analysis
Descriptive statistics (average value, standard deviation, maximum value, minimum value) was assessed using Microsoft Excel 2016 software. For the determination of a significant difference between treatments (different combinations of three factors:

Statistical Analysis
Descriptive statistics (average value, standard deviation, maximum value, minimum value) was assessed using Microsoft Excel 2016 software. For the determination of a significant difference between treatments (different combinations of three factors: research date, tillage-fertilization system, and biochar rate) hydro-physical and chemical properties the three-factorial ANOVA was performed (package STATISTICA Base (version 6). Differences among studied groups were significant at p < 0.05 and p < 0.01. Additionally, the least significant difference (LSD 05 ) was presented [29]. Correlation between soil hydro-physical and chemical properties and wettability which was expressed as intensity of absorption in hydrophilic functional groups was performed using Pearson correlation analysis [34]. Pearson's correlation analysis of hydro-physical and chemical properties (soil organic matter, pH, electrical conductivity, water holding capacity, and moisture content) and C-O functional group intensity (a.u.) of soil were conducted using the SPSS software package (SPSS Inc., Chicago, IL, USA).

Soil Organic Matter Content
Assessing the effect of time on soil organic matter (SOM) content, average data showed that after 24 months it was 6.14% lower than after 3 months, but 26% higher than after 12 months. Fertilization with nitrogen, phosphorus, and potassium (NPK) fertilizers resulted in higher SOM, which was 10.4% and 26.6% higher to unfertilized soil groups (in S and M tillage systems, respectively). On average, the application of 5 t/ha biochar dose increased SOM by 19.7%, and 15 t/ha by 33.7%, compared to the control groups (without biochar) ( Figure 5). The influence of biochar dose on SOM was significant in all tillage-fertiliza systems (p < 0.05) ( Table 2). Biochar usage in a direct drilling system (M) was m promising and had a greater effect on SOM compared to shallow ploughless tillage ( in the S system 5 t/ha biochar dose increased SOM by 5.63-11.7%, and the rate of 15 t/h by 26.9-22.2% (in S-1 and S-2 systems, respectively), then in the M system-18-41.3% 29-54.8% (in M-1 and M-2 systems, respectively) compared to variants without bioc 15 t/ha biochar dose determined the best SOM conditions only when it was use combination with mineral fertilizers in both tillage systems (S-4.89% and M-6.4 respectively). Regardless of the tillage-fertilization system, the biochar effect on SOM most promising after 6 months, since SOM content was 51.6-75.5% higher in all vari The influence of biochar dose on SOM was significant in all tillage-fertilization systems (p < 0.05) ( Table 2). Biochar usage in a direct drilling system (M) was more promising and had a greater effect on SOM compared to shallow ploughless tillage (S). If in the S system 5 t/ha biochar dose increased SOM by 5.63-11.7%, and the rate of 15 t/ha-by 26.9-22.2% (in S-1 and S-2 systems, respectively), then in the M system-18-41.3% and 29-54.8% (in M-1 and M-2 systems, respectively) compared to variants without biochar. 15 t/ha biochar dose determined the best SOM conditions only when it was used in combination with mineral fertilizers in both tillage systems (S-4.89% and M-6.48%, respectively). Regardless of the tillage-fertilization system, the biochar effect on SOM was most promising after 6 months, since SOM content was 51.6-75.5% higher in all variants compared to variants without biochar addition. After 3, 6, 12, and 24 months, variant with direct drilling + fertilization + 15 t/ha biochar dose (M-2) had the highest SOM (6.69%; 10.9%; 3.72%; 5.01%, respectively).

Soil pH
Based on the average data, after 24 months soil pH was 11.8% higher than after 3 months. Fertilization with NPK fertilizers resulted in lower pH, which was 13.6% and 16.9% lower in the fertilized groups compared to unfertilized (in S and M systems, respectively). A 5 t/ha biochar dose increased soil pH by 1.72% and 15 t/ha-by 6.84%, compared to the variants without biochar ( Figure 6).

Soil pH
Based on the average data, after 24 months soil pH was 11.8% higher than after 3 months. Fertilization with NPK fertilizers resulted in lower pH, which was 13.6% and 16.9% lower in the fertilized groups compared to unfertilized (in S and M systems, respectively). A 5 t/ha biochar dose increased soil pH by 1.72% and 15 t/ha-by 6.84%, compared to the variants without biochar ( Figure 6). Regardless of the tillage-fertilization system, after 3, 6, 12, and 24 months 15 t/ha biochar dose increased soil pH by 12.5%, 5.88%, 5.75%, and 3.98%, respectively. Biochar effect on soil pH was significant in all tillage-fertilization systems (p < 0.05) ( Table 3). Biochar usage in the M system was more promising than in S. In the M system 15 t/ha biochar dose increased soil pH by 8.79-19.1% (M-1 and M-2) compared to the control group. After 6, 12, and 24 months of biochar incorporation, direct drilling soil had the highest pH (7.31; 7.82; 7.99, respectively).  Regardless of the tillage-fertilization system, after 3, 6, 12, and 24 months 15 t/ha biochar dose increased soil pH by 12.5%, 5.88%, 5.75%, and 3.98%, respectively. Biochar effect on soil pH was significant in all tillage-fertilization systems (p < 0.05) ( Table 3). Biochar usage in the M system was more promising than in S. In the M system 15 t/ha biochar dose increased soil pH by 8.79-19.1% (M-1 and M-2) compared to the control group.

Soil Electrical Conductivity
After 24 months soil electrical conductivity (EC) was on average 82.3% lower than after 3 months. Fertilization with NPK fertilizers resulted in higher soil EC. Fertilization governed 82.1% and 141% higher soil EC compared to unfertilized soil (in S and M systems, respectively). A 5 t/ha biochar dose increased EC by 13% and 15 t/ha-by 23.4%, compared to the variants without biochar (Figure 7). governed 82.1% and 141% higher soil EC compared to unfertilized soil (in S a systems, respectively). A 5 t/ha biochar dose increased EC by 13% and 15 t/ha-by 2 compared to the variants without biochar (Figure 7). Regardless of the tillage-fertilization system, after 12 months 5 t/ha and 1 biochar doses increased soil EC by 9.15-21.6%. The influence of biochar on soil E essential in all tillage-fertilization systems (p < 0.05) ( Table 4). 15 t/ha biochar increased soil EC by 28.3-15.8% in the S system (both without fertilization fertilization, respectively), and in the M system-by 33.9-23.8% compared to va without biochar. Usage of a 15 t/ha biochar dose in combination with mineral fert determined the highest soil EC in the M system (289 µs/cm). After 3 and 24 month biochar incorporation, soil variant with direct drilling + fertilization + 15 t/ha biocha had the highest EC (752 µs/cm; 137.6 µs/cm).  Regardless of the tillage-fertilization system, after 12 months 5 t/ha and 15 t/ha biochar doses increased soil EC by 9.15-21.6%. The influence of biochar on soil EC was essential in all tillage-fertilization systems (p < 0.05) ( Table 4). 15 t/ha biochar dose increased soil EC by 28.3-15.8% in the S system (both without fertilization and fertilization, respectively), and in the M system-by 33.9-23.8% compared to variants without biochar. Usage of a 15 t/ha biochar dose in combination with mineral fertilizers determined the highest soil EC in the  Thus, the results demonstrate that tillage and fertilization, by directly determining the physical condition of the soil, also determine its electrical conductivity and plant nutrition conditions. Both soil type and land usage have a significant influence on the overall macroporosity, its surface area, and the distribution of pores belonging to the macropore group. Accordingly, the number of macropores, as well as the number of mesopores and their distribution, is an important factor in determining the amount of water in those pores and their electrical conductivity [35,36].
Based on the soil salinity classes, the studied soil groups were characterized as nonsaline, as EC values for all groups ranged from 0 to 2 dS/m (from 0.04 dS/m in M-1 after 12 months to 0.75 dS/m in M-2 after 3 months). Soils with an EC less than 2 dS/m are considered non-saline and this does not affect many cereal yields and soil microbiological processes. Even mild to moderate salinity can inhibit grain growth. Salts are a natural component of the soil, but when the concentration of salts in the soil is high, especially close to the roots of plants, the roots attract and absorb less moisture [37]. When the salinity of the soil is high enough, the plant will dry out and die, regardless of the amount of extra water used.

Surface Functional Groups of Soil
According to the results of FTIR analysis, after 3 months from biochar application, in both S and M systems, FTIR spectra were similar and had such functional groups: alcoholic -OH (3626 cm −1 ), alkoxy C-O (1023-1084 cm −1 ), aromatic C-H (777-873 cm −1 ) and C=C (1643 cm −1 ) (Figure 8). Comparing fertilized soils amended with different biochar rates, it was observed that in both tillage systems the 5 t/ha biochar rate caused the highest number of functional groups (due to the higher intensity of infrared radiation absorption) and 15 t/ha rate determined the least amount. Meanwhile, in unfertilized soil of the S system, absorption peaks were stronger at 1023-1084 cm −1 and 466-522 cm −1 wavenumbers under 5 t/ha rate application. In the M system, all absorption peaks were stronger when a 15 t/ha biochar rate was used. We suppose that soil fertilization governs more stable soil structure in different soil tillage systems irrespective of biochar application; meanwhile, the chemical structure of unfertilized soil strongly varied independently of the biochar rate. and 15 t/ha rate determined the least amount. Meanwhile, in unfertilized soil of the S sys-tem, absorption peaks were stronger at 1023-1084 cm −1 and 466-522 cm −1 wavenumbers under 5 t/ha rate application. In the M system, all absorption peaks were stronger when a 15 t/ha biochar rate was used. We suppose that soil fertilization governs more stable soil structure in different soil tillage systems irrespective of biochar application; meanwhile, the chemical structure of unfertilized soil strongly varied independently of the biochar rate. The -OH group in soil is related with kaolinite clay minerals (3694, 3620, 3526 cm −1 ), Si-O group with silicates (1031 cm −1 ) and Al-Al-OH with aluminium compounds (913 cm −1 ) [38]. Similarly, in this study, peaks at 3626, 3416, 1023, and 873 cm −1 wavenumbers were observed and it shows the existence of O, H, Al, and Si compounds in the soil structure. The peak at 471 cm −1 wavenumbers is related to the amount of Si [39]. FTIR spectra of soils showed deposition of aluminosilicates on the incorporated biochar. FTIR spectra demonstrate that all studied soil groups undistinguished of hydrophobic C-H methyl and methylene functional groups (absence of peaks at 2920 cm −1 and 2860 cm −1 , respectively [40]). Meanwhile, C-O functional groups (peaks occur at 1600-1740 cm −1 wavenumbers) are related to hydrophilicity. In our experiment, they were found in all soil groups (peaks at 1643 cm −1 wavenumber). Soil hydrophilicity increases with an increase in the density of polar functional groups (such as -OH, -COOH, and -NH 2 ), but decreases with the increase of density of nonpolar functional groups (-CH 3 and =CH 2 ) [41].

Soil Water Holding Capacity
After 24 months, soil water holding capacity (WHC) was on average 29.6% higher than after 3 months. Fertilization resulted in a slightly higher soil WHC in the M system, which was 0.72% higher than without fertilization. Incorporation of 5 t/ha biochar dose increased WHC by 4.27% and 15 t/ha by 8.48%, compared to the variants without biochar (Figure 9).
Regardless of the tillage-fertilization system, after 3, 6, 12, and 24 months 15 t/ha biochar dose increased WHC significantly more than 5 t/ha (by 16.2%, 3.18%, 6.88%, and 9.25%). Thus, the positive effect of both doses on the increase in soil WHC continued-it remained significantly higher at a 15 t/ha dose. The influence of biochar on WHC was significant in all tillage-fertilization systems (p < 0.05) ( Table 5). The usage of biochar in M was more promising for increasing WHC. In the S system (both without fertilization and fertilization), 15 t/ha biochar dose increased WHC by 12.4-5.69% in the M system in comparison with variants without biochar. After 3, 12, and 24 months, the variant with direct drilling + 15 t/ha biochar dose had the highest WHC (54.4%, 61.1%, 67.2%). In summary, it can be seen that over time, soil WHC enhancement by biochar gradually increases.

Soil Water Holding Capacity
After 24 months, soil water holding capacity (WHC) was on average 29.6% h than after 3 months. Fertilization resulted in a slightly higher soil WHC in the M sy which was 0.72% higher than without fertilization. Incorporation of 5 t/ha biocha increased WHC by 4.27% and 15 t/ha by 8.48%, compared to the variants without b (Figure 9). Regardless of the tillage-fertilization system, after 3, 6, 12, and 24 months 15 t/ ochar dose increased WHC significantly more than 5 t/ha (by 16.2%, 3.18%, 6.88% 9.25%). Thus, the positive effect of both doses on the increase in soil WHC continu remained significantly higher at a 15 t/ha dose. The influence of biochar on WH significant in all tillage-fertilization systems (p < 0.05) ( Table 5). The usage of biocha was more promising for increasing WHC. In the S system (both without fertilizatio fertilization), 15 t/ha biochar dose increased WHC by 12.4-5.69% in the M system in parison with variants without biochar. After 3, 12, and 24 months, the variant with drilling + 15 t/ha biochar dose had the highest WHC (54.4%, 61.1%, 67.2%). In sum it can be seen that over time, soil WHC enhancement by biochar gradually increase  It is known that WHC and water availability to plants in clayey and sandy loams can be improved with biochar addition [42]. A study driven by Yu et al. [43] showed that a high percentage of biochar in soil mixture dramatically increases soil WHC. These results suggest that biochar has the potential to mitigate droughts and increase crop yields in sandy loam [43]. Novak et al. [44] reported an increase in the WHC of sandy loam with 2% of biochar made from grass. It was estimated that when the sandy loam WHC was 16%, yellow pine biochar was able to retain 2.7 times its mass (=270%). A study driven by Yu et al. [43] showed that biochar increased soil WHC by 1.7% of its mass each time 1% biochar was added. The results of these studies are important since biochar is an efficient medium for increasing soil irrigation efficiency, mitigating runoff, and reducing non-point agricultural pollution. The ability of biochar to increase soil WHC is particularly important in drought-prone areas. Some studies have not shown a significant effect of biochar incorporation on moisture retention in sandy loam and coarse-textured sandy soil in field studies. This may have been due to the special hydrophobicity of the biochar, which prevented water from infiltrating the biochar pores. The efficiency of biochar in increasing soil water retention will decrease if biochar is hydrophobic; however, the hydrophobicity of biochar is often removed after environmental exposure.
When assessing the impact of tillage methods on increasing soil WHC, some studies indicate that non-cultivated agriculture is more favorable. An 8-year study driven by Raczkowski et al. [45] evaluating sandy loam showed that no-till farming developed higher bulk density, lower total porosity, and macroporosity, but higher capillary porosity (microporosity) and WHC than conventional farming.

Soil Moisture Content
Based on average data, after 24 months, soil moisture content (MC) was 872% higher than after 3 months. Fertilization resulted in 6.52% higher MC in the M system than without fertilization. In the shallow ploughless tillage system, MC was on average 7.36% lower in fertilized soil compared without fertilization. The incorporation of 5 t/ha biochar increased MC by 10.7% and 15 t/ha-by 21.8%, compared to the variants without biochar (Figure 10). Regardless of the tillage-fertilization system, after 3, 6, 12, and 24 months, 15 t/ha biochar dose increased MC significantly more compared to 5 t/ha dose (by 133%; 52.9%; 13.8%; 14.8%). The influence of biochar on MC was significant in all tillage-fertilization systems (p < 0.05), except for the combined effect of different factors ( Table 6). The usage of biochar in the M system was more promising for increasing soil MC than S. If in the shallow ploughless tillage + fertilization system 15 t/ha biochar dose increased MC by 21.2%, then in the direct drilling system-by 27.7% compared to variants without biochar. After 3, 6 and 12 months the highest soil MC was obtained with direct drilling + fertilization + 15 t/ha biochar dose (1.8%; 7.28%; 16.9%). Soil moisture retention is generally higher in a no-tillage system than in conventional tillage. Non-arable agriculture has the advantage of preserving the soil from wind erosion and promoting the retention of soil moisture.  Regardless of the tillage-fertilization system, after 3, 6, 12, and 24 months, 15 t/ha biochar dose increased MC significantly more compared to 5 t/ha dose (by 133%; 52.9%; 13.8%; 14.8%). The influence of biochar on MC was significant in all tillage-fertilization systems (p < 0.05), except for the combined effect of different factors ( Table 6). The usage of biochar in the M system was more promising for increasing soil MC than S. If in the shallow ploughless tillage + fertilization system 15 t/ha biochar dose increased MC by 21.2%, then in the direct drilling system-by 27.7% compared to variants without biochar. After 3, 6 and 12 months the highest soil MC was obtained with direct drilling + fertilization + 15 t/ha biochar dose (1.8%; 7.28%; 16.9%). Soil moisture retention is generally higher in a no-tillage system than in conventional tillage. Non-arable agriculture has the advantage of preserving the soil from wind erosion and promoting the retention of soil moisture.

Soil Wettability
Based on soil wettability results, it can be seen that all the studied soil groups in M and S systems showed high wettability (WDPT ≤ 1 s) or slight hydrophobicity (WDPT = 2) after 6 months and after 12 months (Table 7). According to Chenu et al. [5], soils with instantaneous wettability (WDPT ≤ 1 s) are considered hydrophilic. It can be stated that the influence of biochar, fertilization, and tillage methods on soil wettability is stable for 6 months period. Other studies have estimated that, over time, soil organic matter fills the pores of biochar and reduces its specific surface area. Ren et al. [46] found that after 0.5 years the surface area of biochar in agricultural soil increased and after 1.5 years decreased. Biochar, which has a higher specific surface area, has better sorption for water. Table 7. Soil wettability assessed by water drop penetration time test under ploughless shallow tillage unfertilized (S-1) and fertilized (S-2), direct drilling unfertilized (M-1) and fertilized (M-2) soil, n = 3. A study driven by Ojeda et al. [47] assessed that after 1 year, the soil-biochar mixture was considered hydrophilic because the contact degree values were less than 90 • . There were no differences between collection times and this suggests that the impact of biochar on soil wettability is stable over a 1-year period. When comparing the control soil with the biochar mixtures, wettability was not significantly affected by the biochar dose.

Triticale Grain Yield and Correlation Analysis
The results showed a significant benefit of soil fertilization with NPK mineral fertilizers for triticale grain yield in both tillage systems ( Figure 11). Significant differences between fertilized and non-fertilized soil groups were found when evaluating both tillage methods (p < 0.05). The highest yield of standard moisture triticale grain (3.51 t/ha) was determined in the system of direct drilling, fertilization, and 15 t/ha biochar dose (Figure 11a). This result may have been due to better nutritional conditions of the plants in the fertilized soil, which was determined by the usage of liquid fertilizers. Macro-(N, P, K, Ca) and microelements (Cu, Mn, Zn, B, Fe, Mo) also play an important role in plant growth and development, which in turn increases plant growth and yield. The incorporation of biochar resulted in an increase in triticale yield in all tillage-fertilization systems, the largest of which was in the case of direct drilling and non-fertilization at 5 and 15 t/ha biochar rates (36.8% and 42.8%, respectively). between fertilized and non-fertilized soil groups were found when evaluating both tillage methods (p < 0.05). The highest yield of standard moisture triticale grain (3.51 t/ha) was determined in the system of direct drilling, fertilization, and 15 t/ha biochar dose ( Figure  11a). This result may have been due to better nutritional conditions of the plants in the fertilized soil, which was determined by the usage of liquid fertilizers. Macro-(N, P, K, Ca) and microelements (Cu, Mn, Zn, B, Fe, Mo) also play an important role in plant growth and development, which in turn increases plant growth and yield. The incorporation of biochar resulted in an increase in triticale yield in all tillage-fertilization systems, the largest of which was in the case of direct drilling and non-fertilization at 5 and 15 t/ha biochar rates (36.8% and 42.8%, respectively). Triticale grain yield, t/ha

Biochar dose, t/ha
Fertilized with NPK Non-fertilized with NPK A study driven by Terzic et al. [48] similarly found that the mean triticale yield was lowest in the unfertilized control group (2.06 t/ha) and significantly higher in the fertilized groups (4.05 t/ha, NP2K effect; 4.11 t/ha, NP1K effect). In the mentioned study, the highest grain yield was obtained in the NP1K variant (120 kg/ha nitrogen fertilizer content; 60 kg/ha phosphorus (P 2 O 5 ) fertilizer content, and 60 kg/ha potassium (K 2 O) fertilizer content). Study driven by Gebremedhin et al. [49] showed that the incorporation of biochar into the soil increases the yield of wheat grain and straw by 15.7% and 16.5%, respectively. A study driven by Bielski et al. [19] showed that the control group (without nitrogen fertilizers), which was 3.17 t/ha, had the lowest triticale yield. The highest yield was observed in the effect group of the highest amount of nitrogen fertilizers (160 kg/ha) in the first study year (2013), which amounted to 5.17 t/ha. The grain yield of winter triticale strongly depended on the weather conditions during the whole study year and on the amount of nitrogen fertilizers. Previous authors pointed out that the triticale yield depended not only on fertilization but also on weather conditions. Some researchers point out that air is one of the most important factors influencing grain yields. A study driven by Gibson et al. [50] showed that the application of nitrogen fertilizers (33 kg/ha) increased the yield of triticale grain by 64% compared to the control group and reached 3.7 mg/ha after 2 years.
Pearson correlation analysis showed a significant relationship between triticale grain yield and its soil electrical conductivity (R = 0.79; R 2 = 0.62; p = 0.002) ( Figure 12). As the electrical conductivity of the soil increased, the yield of triticale also increased. Soil electrical conductivity can provide guidelines for assessing soil productivity. Therefore, in the future, it is necessary to clarify the mechanisms between the transfer of macroand micronutrients to agricultural crops from soils improved with mineral fertilizers in combination with biochar. yield and its soil electrical conductivity (R = 0.79; R 2 = 0.62; p = 0.002) ( Figure 12). As the electrical conductivity of the soil increased, the yield of triticale also increased. Soil electrical conductivity can provide guidelines for assessing soil productivity. Therefore, in the future, it is necessary to clarify the mechanisms between the transfer of macro-and micronutrients to agricultural crops from soils improved with mineral fertilizers in combination with biochar. Plant yields strongly depend on the soil conditions in which the plant root system develops. The quality of soil conditions is defined as the appropriate air-water regime, mechanical composition, and soil nutrient resources [51]. A study driven by Zhao et al. [52] showed that there was a linear correlation between soil electrical conductivity and winter wheat yield at different wheat growth stages. The coefficients of determination of the models were all greater than 0.63. The strength and direction of the relationship between cereal yield and soil electrical conductivity depend on the amount of precipitation encountered in the early growing season. Cereal yields correlated strongly and negatively with electrical conductivity when there was low precipitation in March. Meanwhile, Plant yields strongly depend on the soil conditions in which the plant root system develops. The quality of soil conditions is defined as the appropriate air-water regime, mechanical composition, and soil nutrient resources [51]. A study driven by Zhao et al. [52] showed that there was a linear correlation between soil electrical conductivity and winter wheat yield at different wheat growth stages. The coefficients of determination of the models were all greater than 0.63. The strength and direction of the relationship between cereal yield and soil electrical conductivity depend on the amount of precipitation encountered in the early growing season. Cereal yields correlated strongly and negatively with electrical conductivity when there was low precipitation in March. Meanwhile, yields were positively or weakly negatively correlated with electrical conductivity when there was low to moderate precipitation in March [53]. Similarly, in this study, in early cultivation, in March, precipitation was on average lower (12.6 mm) than in July (22 mm) or August (35.7 mm), and lower precipitation in spring can be attributed to a strong positive soil electrical conductivity and correlation of triticale yield. Higher nutritional values of soil may be due to higher nutrient levels, so a positive relationship between cereal yield and soil electrical conductivity can also be attributed to potentially higher nutrient levels. This is because the soil can conduct an electric current due to the movement of ions in solution, and these mobile ions are determined by the availability of nutrients as a function of crop yield. Thus, the electrical conductivity of the soil is expected to be higher where the concentration of nutrients required for crop growth and yield is higher.

Discussion and Future Research
Previous studies found that more hydrophobic soils have a higher amount of organic matter. According to the study of Mirbabaei et al. [54], SOM, soil texture, and pH revealed significant relation with its hydrophobicity. The positive correlation (r = 0.42) between logWDPT and the amount of SOM was found in all tested samples. Other studies found a positive correlation between the amount of organic matter and hydrophobicity in clay soil from the Utah State (USA) [55], in pine forest soil affected by wildfires from Spain [56] and in Mexican volcanic soils as well [57]. Though Vogelmann et al. [6] determined very small coefficients between SOM and hydrophobicity; they concluded that soils were more hydrophobic having a higher amount of organic matter. In this study, irrespective of SOM content in sandy loam soil and tillage-fertilization practice, the soil was hydrophilic during the whole period of investigations. It can be explained by their similar chemical composition in which oxidized aluminum and silica components and hydrophilic C-O groups dominated, according to the molecular spectrometric method.
The soil moisture content (MC) is usually determined by the soil texture and precipitation. Previous studies found a positive impact of biochar on the soil MC and increase of